What are two roles of Domain Name Services (DNS)? (Choose Two)
A.builds a flat structure of DNS names for more efficient IP operations B.encrypts network Traffic as it travels across a WAN by default C.improves security by protecting IP addresses under Fully Qualified Domain Names (FQDNs) D.enables applications to identify resources by name instead of IP address E.allows a single host name to be shared across more than one IP address正确答案DE